Each ZFS component, such as datasets and pools, must be named according to the following rules:
Each component can only contain alphanumeric characters in addition to the following four special characters:
Pool names must begin with a letter, and can only contain alphanumeric characters as well as underscore (_), dash (-), and period (.). Note the following pool name restrictions:
The beginning sequence c[0-9] is not allowed.
The name log is reserved.
A name that begins with mirror, raidz, raidz1, raidz2, raidz3, or spare is not allowed because these names are reserved.
Pool names must not contain a percent sign (%).
Dataset names must begin with an alphanumeric character.
Dataset names must not contain a percent sign (%).
In addition, empty components are not allowed.